Testing connectivity on long cable runs

[ChadTower]

So, I got the Rg6 and cat6 wires run from my basement, through the wall, to the bedroom above.

So far I have had the chance to test the RG6 wires only.

One of the two RG6 lines comes through fine, I see the satellite signal on it.  According to the Tivo, the other line is not delivering signal.  I'm going to swap out the 6' line from the wall jack to the Tivo itself, but assuming for now that that is good...

... what is the best way to simply run a continuity check on the RG6 line, given that one end is in the basement and the other end is upstairs?  Maybe there is a break in the copper line someplace.

[ErikRuud]

I am asuuming that you have a continuity tester/multi meter.

At one of my first jobs, we used to check continuity on long coax runs for 3270 dumb terminals by shorting out one end of the run so we could check the continuity from the other end.

[ChadTower]

I do have a multimeter, but I'm not sure how I would short out the other end...

[quarterback]

When I ran Cat5 in my house, I got a tester along with my box-o-cable and crimper.  My tester looks something like this:



http://www.technologydepot.net/NETWORK-Network_Cable_Tester_with_RJ_45_Crimping_Tool.html

[quarterback]

If you want to use a multimeter to test from one end, you could build a female connection pigtail for one end.  Then, one by one, short the wires coming off the pigtail.  Attach 1 to 2, then 1 to 3, then 1 to 4 etc.  Then, at the other end of things, use your continuity tester by touching 1 and 2, 1 and 3, 1 and 4 etc 

You'll have to run back and forth each time to disconnect and reconnect each pair, but it should let you track down a possible break somewhere.   Although honestly, the first thing I'd do is to cut off the ends of the existing cable and re-crimp a new connector.  For me, any problems have been related to my crimping and not a broken wire in the middle of things.

[ErikRuud]

He is asking about RG6 which only has two conductors.

Chad, use a piece of wire to connect the center conductor to the outer ring.

[ChadTower]

Yeah, a cable tester won't do a ton of good since the problem line is rg6 and not cat6.

The cable that is not working was pretty thick.

[Ed_McCarron]

"Would the multimeter send enough current that it would work over a 50 foot run?"

Yes.  You'd look for a resistance, probably about 5-10 ohms, most likely less.  Only problem with that is if theres a short in the cable.

Test twice:  Once with no shorting jumper, verifying an open - no shorts anywhere.  Then test with the shorting jumper, looking for low resistance.

This should tell you go/no go at least, or where to look for problems.

[quarterback]

He is asking about RG6 which only has two conductors.

DOH!  Sorry

[Harry Potter]

Should be no probs with the current. I've done similar things with 20 meter (about 70 feet) lenghts of coax when seting up a very primitive network ages ago.
And don't forget to set the multimeter to beep or buzz. But you probably knew this already. 

[ChadTower]

Yeah, the pocket multimeter I have has a continuity setting.

I have to figure out how to use the other 2-3 multimeters I just picked up.

[ChadTower]

Question:  If too much of the outer braid were scraped away during crimping, would this cause the cable to not transmit properly?

Probably, yes, from my research, but figured I'd check.

[Harry Potter]

Not really. Unless it made contact with the core. You should get an itermittent signal at best.

Oh I forgot to ask. TiVo uses a digital signal right?

[ChadTower]

Yeah, it's a satellite receiver first, Tivo second.  That would make it purely digital.

So, I guess a more accurate desc would be "I'm running two lines for a satellite receiver".

I'm reading up on coax now.  From the descs of the RG designations there I'm starting to suspect the guy at Home Depot gave me quad shield rather than normal RG6 like I asked.  It is definitely thicker than the first run I did with regular RG6.  It was really hard, and took a bit of hacking, to get the RG6 connector on either end.

I suspect my problem is that I need to use RG6 quad shield connectors rather than regular RG6.  The outer conductor ring in the connector was just too narrow for this cable and it is probably sitting in the stupid foam instead of on the braid.